Google is offering free additional 2 Gigabytes of storage if you observe Safer Internet Day by taking two minutes to check the security of your Gmail or Google Apps for Work account. This is the second year Google has made this offer. To get your free additional 2 Gigabytes simply go through the steps by using the Security Checkup by February 17, 2016.
Google is tough on security so you need to follow the recommended security steps using:
Reviewing Recent Sign in Activity
Confirming what apps and devices are using your account
Reviewing 2 Step Verification
If you take the two minute security check steps your additional 2 Gigabytes will be added immediately or by the end of February to your Google Drive Storage. You can continue to use the Security Checkup after February 17, 2016 to check your Gmail security.